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feedmeister

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## Homework Statement

Figure 16.69

A thin spherical shell made of plastic carries a uniformly distributed negative charge -7e-10 coulombs (indicated as -Q1 in the diagram). Two large thin disks made of glass carry uniformly distributed positive and negative charges 1.7e-05 coulombs and -1.7e-05 coulombs (indicated as +Q2 and -Q2 in Figure 16.69). The radius R1 of the plastic spherical shell is 7 mm, and the radius R2 of the glass disks is 4 meters. The distance d from the center of the spherical shell to the positive disk is 19 mm.

(a) Find the potential difference V1 - V2. Point 1 is at the center of the plastic sphere, and point 2 is just outside the sphere.

volts

(b) Find the potential difference V2 - V3. Point 2 is just below the sphere, and point 3 is right beside the positive glass disk.

volts

Remember that the sign of the potential difference is important.

## Homework Equations

E = (Q/A)/E_o

## The Attempt at a Solution

I tried calculating the field from the capacitor and multiplying it, but I really think I'm going in circles. Anyone help?

I'm so confused on how to begin... Please help.